var argvArr=process.argv;
var myorder1=argvArr[2];
var myorder2=argvArr[3];
var myorder3=argvArr[4];
if(myorder1==null||myorder1=="--help"||myorder1=="--h"){
    console.log("程序使用说明：");
}
if(!/^\d+$/.test(myorder1)||!/^\d+$/.test(myorder3)){
    console.log("输入数据错误！");
}

if(myorder2=="+"){
        console.log(parseInt(myorder1)+parseInt(myorder3));
}
else if(myorder2=="-"){
    console.log(parseInt(myorder1)-parseInt(myorder3));
}
else if(myorder2=="*"){
    console.log(parseInt(myorder1)*parseInt(myorder3));
}
else if(myorder2=="/"){
    console.log(parseInt(myorder1)/parseInt(myorder3));
}

